Container with thermal storage member

ABSTRACT

A container assembly has a substantially rigid moulded plastic shell, tub, a lid, and an auxiliary container that may contain a thermal storage medium such as a phase change liquid. The lid has a peripheral seal that mates in an interference fit with the lip of the tub. The lid also has external fittings that define a seat for the auxiliary container. The lid and the auxiliary container have mutually engaging guides and guide followers that permit a single degree of translational freedom sliding motion of the auxiliary container relative to the lid. The fittings of the seat and the interference fit seal fittings of the lid and the tub do not interfere with or obstruct each other. The tub, the lid and the auxiliary container may have roughly the same footprint, such that when assembled they form a compact assembly, one atop, or beside, the other. That assembly may fit inside an accommodation of an associated soft-sided insulated wall structure such as may define a lunch container or carrier, or other soft-sided insulated package.

FIELD OF THE INVENTION

This invention relates to the field of portable containers.

BACKGROUND OF THE INVENTION

Insulated containers have become popular for carrying either articles that may best be served cool, such as beverages or salads, or warm, such as appetizers, and so on. Often such containers are used for carrying children's lunches as when at school. These containers may include substantially rigid tubs or bowls which may included sealable lids. Often the tub is made of a relatively rigid plastic, while the lid is made of a more pliable plastic. Typically, the tub or base container portion has a lip and the lid has a mating groove, the one fitting the other, often in an elastic interference fit such that when the two are mated together a seal may be formed. The seal may be (within reason) substantially watertight. Most classically products of this nature were introduced by, or made prominent in the market under the brand name Tupperware™.

Soft-sided insulated containers have the advantage of being relatively light, and so therefore relatively easily carried, and relatively forgiving in terms of imparting damage to the objects placed within them. However, it may be desirable to obtain the insulative benefit of a soft-sided insulated container, in combination with a light weight, internal substantially rigid container that fits inside the outer soft-sided container, or that may provide a stand alone container having a substantially rigid body. Such containers are frequently used to carry liquids, whether hot liquids, such as soup containers, coffee or tea, or cold liquids such as beer, soft drinks, or other carbonated beverages, juices and milk, or objects that one may wish to avoid crushing. Sometimes these containers may by used to carry lunches, which may include a sandwich, fruit, carrot and celery sticks, a drink, cookies, and so on. The soft-sided container may have a compartment for the substantially rigid container, as well as other compartments with or without a substantially rigid member.

It may be desired that the container include a thermal storage member, be it an ice pack, or a member that, on shaking or other manipulation, is exothermic, and may provide warming to objects contained therewithin, or adjacent thereto. However, cooling packs (as they most normally may be) tend to present a number of convenience, use, and packaging issues. The present inventor provides a thermal storage package for use in conjunction with a container that may tend to address these issues.

SUMMARY OF THE INVENTION

In an aspect of the invention there is a container assembly. It includes a base portion, a lid portion, and an auxiliary container. The base portion has a generally rectangular first wall and a peripheral sidewall standing away therefrom. The peripheral sidewall has four co-operating generally four sided portions, the base wall and the sidewalls co-operating to define an open topped box-like tub. The peripheral sidewall has a peripheral lip defining an opening of the box-like tub. The lid portion includes a substantially planar spanning member. The substantially planar member has a first face for orientation, in use, toward the tub, a second face for orientation away from the tub, and a neutral plane. The lid portion has a peripheral land facing in the same orientation as the first face of the spanning member. The peripheral land is matingly engageable with the lip of the base portion. The lid is movable between an open position in which the land and the lip are disengaged, and a closed position in which the land and the lip are engaged. In the closed position the lid and the base portion defining an enclosed chamber. The auxiliary container has a hollow body, and a port by which liquids may be introduced therewithin, the port has a closure member. The auxiliary container has a length, a breadth, and a through-thickness. The length is at least as great as the breadth, and the through-thickness is less than one half of each of (a) the length and (b) the breadth. The auxiliary container has a surface for placement next to the spanning member. The lid has a seat for the auxiliary container. One of (a) the lid and (b) the auxiliary container, has at least one guide; the other of (a) the auxiliary container, and (b) the lid, has at least one guide follower, the guide and guide follower being co-operable to direct the auxiliary container into an engaged position in the seat. The lid is engageable with the lip by an engagement motion in a first direction. The auxiliary container is movable into engagement with the seat by motion in a second direction. The auxiliary container is constrained to move in the second direction by the at least one guide and guide follower. The second direction is substantially cross-wise to the first direction; and, when the auxiliary container is mounted in the seat engagement of the lip with the peripheral land is unobstructed by the auxiliary container, the at least one guide and the at least one guide follower.

In a feature of that aspect of the invention, the auxiliary container has a substantially rectangular footprint, and includes first and second flange portions extending outwardly from at least two opposed edges of the rectangular footprint. The lid has first and second opposed mating flanges for sliding engagement with the first and second flange portions of the auxiliary container, the flange portions and the flanges defining the at least one guide and the at least one guide follower. In another feature the auxiliary container has a phase change thermal storage medium contained therewithin. In still another feature the auxiliary container has a first substantially rectangular wall, a second substantially rectangular wall spaced and parallel to the first rectangular wall, and a peripheral wall extending between the first and second substantially rectangular walls. The first wall has first and second extending flange portions standing proud of the peripheral wall, the flange portions defining the at least one guide follower. The lid includes a set of cleats, the cleats defining the at least one guide member. The cleats are mounted to stand proud of the second face of the spanning portion of the lid. The cleats and the flange portions is co-operable in a sliding interference fit. In yet another feature the open-topped box-like tub includes a seat for receiving the auxiliary container therewithin, and, when the auxiliary container is received therein, the lid and lip are unobstructed. In a further feature, the auxiliary container, the lid portion, and the base portion all have generally corresponding footprints.

In a still further feature, the apparatus includes a soft-sided insulated container housing, the housing including an accommodation of a close fitting size corresponding to the auxiliary container, the lid portion and the base portion as assembled, the soft-sided insulated container housing is made of a wall structure has an inner skin, an outer skin and a layer of thermal insulation therebetween. In a further additional feature, the soft-sided insulated container includes a first soft-sided insulated wall portion defining a first compartment and a second soft-sided insulated wall portion defining a second compartment. The first compartment defines the accommodation. The first compartment has a first closure member. The second compartment is mounted adjacent to the first compartment, and has a second closure member governing access thereto, the first and second compartments sharing, and is segregated by, a common wall. In a still yet further feature, the soft-sided insulated container includes a lifting member, and, in use, when hanging from the lifting member, the first compartment is located below the second compartment, and the second compartment narrows from a broad base to a narrow top.

In another aspect of the invention there is a container assembly that includes a first member, a second member, and a third member. The first member is a substantially rigid container base portion, the base portion has a bottom and an upstanding peripheral sidewall. The upstanding peripheral sidewall has a margin defining a lip. The second member is a substantially planar lid co-operable with the container base portion. The lid includes a peripherally extending land matable with the lip. The lip and the land mate in an elastic interference fit defining a seal such that the lid is co-operable with the container base portion. The third member is a substantially rigid hollow vessel. The third member has an internal volumetric envelope, a nominal enclosed surface and a first surface for placement next to the second member. The first surface has an hydraulic diameter has a magnitude that is greater than the cube root of the internal volume. The first surface has an area greater than one sixth of the nominal enclosed surface. The second member has a seat for receiving the third member, and when so seated, the first surface is next to the second member, the second and third members have between them a co-operable set of guides and guide followers by which the second member is moved between engaged and disengaged positions relative to the seat; and the land is unobstructed by (a) the seat; (b) the guides and (c) the guide followers.

In a feature of that aspect of the invention the container assembly further includes a soft-sided insulated container has a first accommodation sized to receive the first, second and third members as an assembled unit. In an additional feature, the soft-sided insulated container has a second accommodation defined therein. In a still further feature, the soft-sided insulated container has a first soft-sided insulated wall structure portion in the form of a five-sided open topped box defining the first accommodation. The second soft-sided insulated wall structure portion has a base, a pair of end walls, and a downwardly opening spanning wall extending between two end walls co-operably joined to define the second accommodation therewithin. The base of the second soft-sided insulated wall structure portion defines a lid of the first soft-sided insulated wall structure portion. The soft-sided insulated wall structure includes a first closure member extending peripherally about at least a portion of the base of the second soft-sided insulated wall structure portion. The first closure member is operable to govern opening and closing of the base relative to the five-sided open-topped box structure, thereby governing entrance thereto. The base has an edge hingedly joined to the five-sided open-topped insulated box. The end walls have a downwardly broadening form that has a crest and a base. The spanning wall is bent to conform to the downwardly broadening form. The second soft-sided insulated wall structure portion includes a second closure member governing access thereto. The soft sided insulated container has a handle mounted at the crest, whereby, when lifted by the handle the first accommodation hangs below the second accommodation.

In another feature the lid mates with the lip by motion predominantly in translation in a first direction substantially normal to the lid; and the substantially rigid hollow member mates with the lid by motion in translation in a direction predominantly parallel to the lid.

In another aspect of the invention, there is a container assembly that includes a plastic moulded tub has a peripheral lip defining a mouth of the tub; a plastic moulded lid for the tub; and a moulded plastic flask. The lid has a closure fitting for mating with the moulded tub. The lid has guide fittings. The moulded plastic flask has guide followers for sliding engagement with the guide fittings of the lid; and when the moulded flask is mated to the lid (a) the closure fitting for mating with the tub is unobstructed by the guide fittings and guide followers; and (b) the guide fittings and guide followers are unobstructed by the closure fitting.

In a feature of that aspect of the invention, the closure fitting and the moulded tub engage by relative motion in a direction substantially normal to the lid, and the flask and the lid engage by motion in a direction substantially parallel to the lid. In another feature, the lid has a first face oriented to face into the tub, and the closure fitting is oriented in the same direction; the lid has a second face oriented to face away from the tub; and the guide fittings stand proud of the second face. In an alternate feature, the tub has at least one abutment fitting defining a seat therein for receiving the flask within the tub without obstructing securement of the lid to the tub. In a further alternate feature, the lid has guideway accommodations for the flask both internally and externally relative to the tub. In another alternate feature, the tub has a base wall, and the base wall has external fittings for mounting the flask in substantially planar facing relationship thereto outside the tub.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the invention may be more readily understood with the aid of the illustrative Figures included herein below, showing of an example, or examples, embodying the various aspects of the invention, provided by way of illustration, but not of limitation of the present invention, and in which:

FIG. 1 shows a isometric view from in front, to one side and above an example of an embodiment of a container assembly according to an aspect of the invention;

FIG. 2 is an opposite isometric view of the container assembly of FIG. 1;

FIG. 3 is a front view of the container assembly of FIG. 1, the rear view being substantially the same but of opposite hand;

FIG. 4 is a left hand end view of the container assembly of FIG. 1;

FIG. 5 is a right hand end view of the container assembly of FIG. 1;

FIG. 6 is a top view of the container assembly of FIG. 1;

FIG. 7 is a bottom view of the container assembly of FIG. 1;

FIG. 8 is a front view of the base portion and lid of the container assembly of FIG. 1 in an open condition, the front view being the same as the rear view, but of opposite hand;

FIG. 9 shows a right hand end view of the base portion and lid of FIG. 8;

FIG. 10 a shows a top view of the lid of FIG. 8;

FIG. 10 b shows a top view of an alternate lid to that of FIG. 8;

FIG. 10 c shows a front view of the lid of FIG. 10 a;

FIG. 10 d shows a front view of the lid of FIG. 10 b;

FIG. 10 e shows a right hand view of the Lid of FIG. 10 a;

FIG. 11 a shows a sectional view of the lid of FIG. 11 a taken on section ‘11 a-11 a’ of FIG. 10 a;

FIG. 11 b shows a sectional view of the lid of FIG. 10 b analogous to the section of FIG. 11 a;

FIG. 11 c shows a sectional view of the lid of FIG. 10 a taken on section ‘11 c-11 c’ of FIG. 10 a;

FIG. 11 d shows sectional view of the lid of FIG. 10 b taken on a section analogous to that of FIG. 11 c;

FIG. 12 a shows a top plan view the auxiliary container for use with the assembly of FIG. 1;

FIG. 12 b shows a bottom plan view of the auxiliary container of FIG. 12 a;

FIG. 12 c shows a right hand side view of the auxiliary container of FIG. 12 a, the left hand side being the same but of opposite hand;

FIG. 12 d shows a first end view of the auxiliary container of FIG. 12 a;

FIG. 12 e shows an opposite end view of the auxiliary container of FIG. 12 a;

FIG. 13 shows an alternate form of container assembly to that of FIG. 1;

FIG. 14 shows a cross-section, analogous to that of FIG. 11 a, of an alternate embodiment of lid to that of FIG. 10 a;

FIG. 15 shows a cross-section of an alternate combination to that of FIG. 1 in which an auxiliary container is mounted inside another container; and

FIG. 16 shows a cross-section of yet a further alternate to that of FIG. 1 in which an auxiliary container is mounted beneath a main container.

FIG. 17 a shows an isometric view, in partial scab section (not to scale) of the container assembly of FIG. 1 as seated in a compartment of a soft-sided insulated container;

FIG. 17 b shows a front view of the soft-sided insulated container of FIG. 17 a;

FIG. 17 c shows a rear view of the soft-sided insulated container of FIG. 17 a;

FIG. 17 d shows a left hand view of the soft-sided insulated container of FIG. 17 a;

FIG. 17 e shows a right hand view of the soft-sided insulated container of FIG. 17 a;

FIG. 17 f shows a top view of the soft-sided insulated container of FIG. 17 a; and

FIG. 17 g shows a bottom view of the soft-sided insulated container of FIG. 17 a.

DETAILED DESCRIPTION

The description that follows, and the embodiments described therein, are provided by way of illustration of an example, or examples, of particular embodiments of the principles of the present invention. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the invention. In the description, like parts are marked throughout the specification and the drawings with the same respective reference numerals. The drawings are substantially to scale, except where noted otherwise, such as in those instances in which proportions may have been exaggerated in order more clearly to depict certain features of the invention.

For the purposes of this description, it may be that a Cartesian frame of reference may be employed. In such a frame of reference, the long, or largest dimension of an object may be considered to extend in the direction of the x-axis, the base of the article, where substantially planar, may be considered to extend in an x-y plane, and the height of the article may be measured in the vertical, or z-direction. The largest panels of the containers described herein may be designated arbitrarily as either the front and rear sides or top and bottom sides, faces, or portions of the container. Similarly, the closure member, or opening is arbitrarily designated as being at the top, and the base panel is designated as being at the bottom, as these terms may be appropriate for the customary orientation in which the objects may usually be found, sold, or employed, notwithstanding that the objects may be picked up and placed on one side or another from time to time at the user's choice. It should also be understood that, within the normal range of temperatures to which human food and human touch is accustomed, although the term cooler, or cooler container, or cooler bag, may be used, such insulated structures may generally also be used to keep food, beverages, or other objects either warm or hot as well as cool, cold, or frozen.

In this specification reference is made to insulated containers. The adjective “insulated” is intended to be given its usual and normal meaning as understood by persons skilled in the art. It is not intended to encompass single layers, or skins, of conventional webbing materials, such as Nylon™, woven polyester, canvas, cotton, burlap, leather, paper and so on, that are not otherwise indicated as having, or being relied upon to have, particular properties as effective thermal insulators other than in the context of being provided with heat transfer resistant materials or features beyond that of the ordinary sheet materials in and of themselves. Following from Phillips v. A WH Corp., this definition provided in the specification is intended to supplant any dictionary definition, and to prevent interpretation in the US Patent Office (or in any other Patent Office) that strays from the customary and ordinary meaning of the term “insulated” as provided herein. The Applicant also explicitly excludes cellophane, waxed paper, tin foil, paper, or other single use disposable (i.e., not intended to be re-used) materials from the definition of “washable”.

Similarly, this description may tend to discuss various embodiments of hard shell containers, as opposed to soft-sided containers. In the jargon of the trade, a soft-sided cooler, or bag, or container, is one that does not have a substantially rigid, high density exoskeleton. A typical example of a container having a hard exoskeleton is on having a molded shell, e.g., of ABS or polyethylene, or other common types of molded plastic. Rather, a soft-sided container may tend not to be substantially rigid, but may rather have a skin that is flexible, or crushable, or sometimes foldable. By way of an example, which is not intended to be either exhaustive, comprehensive, exclusive or limiting, a soft-sided cooler may have an outer skin, a layer of insulation, and an internal skin, both the internal and external skins being of some kind of webbing, be it a woven fabric, a nylon sheet, or some other membrane. The layer of insulation, which may be a sandwich of various components, is typically a flexible or resilient layer, perhaps of a relatively soft and flexible foam. In some examples, a soft-sided container may still be a soft-sided container where, as described herein, it may include a substantially rigid liner, or may include one or more battens (which may be of a relatively hard plastic) concealed within the soft sided wall structure more generally, or where hard molded fittings may be used either at a container rim or lip, or to provided a base or a mounting point for wheels, but where the outside of the assembly is predominantly of soft-sided panels. Once again, this commentary is intended to forestall the adoption by the US Patent Office, (or any other Patent Office), of an interpretation of the term “soft-sided” that diverges from the ordinary and customary meaning of the term as understood by persons of ordinary skill in the art in the industry, and as used herein.

To commence, the Figures illustrate a container assembly, in dicated generally as 20. Container assembly 20 includes a first member, such as may be a substantially rigid vessel, which may be termed variously a receptacle, an accommodation, a box-lik structure, a box, a bin, an opentopped container, or, more simply, a tub, and, under any of these names, may be identified in the illustrations as item 22; a second member, such as may be a closure member or adapter, a top, a lid member, or more simply a lid, and which, under any of these names is identified in the illustrations as item 24; and a third member, such as may be another vessel such as may be in the nature of a flask 26 which may be used to contain a thermal energy storage medium, which may be a phase change medium, as discussed below. The assembly may also include, or itself be part of, an assembly that includes a soft-sided insulated container, identified generally as item 30 and shown in FIGS. 16 a-16 g.

Considering the first member, namely vessel 22, this vessel may have a lower portion, or base, or bottom wall panel, upon which it may tend to sit in the normal course of use; and an upper portion that extends away from the lower portion. For example, the lower portion may include a bottom wall 32 which may have a generally four sided, square or rectangular plan view footprint. The square or rectangular shape may include two pairs of opposed side edges, which, in the case of a rectangle, may include a pair of first and second short sides and a pair of first and second long sides. A peripheral wall 34 may extend predominantly upwardly and away from bottom wall 32. Peripheral wall 34 may include four side portions 35, 36, 37, and 38 each of which extends from one of the edges of bottom wall 32. Each of side portions 35, 36, 37 and 38 may itself be four sided, and may be generally rectangular in shape. To the extent that peripheral wall 34 is tapered to facilitate moulding or stacking, those sides, although generally rectangular may actually be trapezoidal, and may have a draft angle, or angle at which they splay outward, indicated as alpha. The side portions and the bottom portion may meet at vertices, and those vertices may be formed on corner radii. Items 32, 35, 36, 37 and 38 co-operate to define a five sided open topped tub or box or receptacle, or container, or tub, according to the chosen terminology. In the context of the present description, the resulting member may be a unitary molded plastic part, the plastic being any of a number of kinds, of which polypropylene may be one, the plastic chosen being one that is suitable for the containment and carriage of foodstuffs. In the example, the proximal edges of the side portions 35, 36, 37 and 38 may adjoin bottom wall 32, the distal edges may co-operate to define a mouth, or lip, or rim or land, for engagement with a closure member. It may be that the lip, indicated as 40 is not merely an in-plane extension of the particular side wall portions of which it forms a marginal part, but rather it may be canted at an angle different from angle alpha, such as angle psi. In the case of FIG. 8, lip 40 may be splayed more pronouncedly outward than the general draft angle of the sides. Although the tub, or receptacle, as it may be termed, may be made of a substantially rigid material, the plastic may also be elastic to a certain extent, such as may facilitate a springy, interference fit. Further, a reinforcement member, such as a flange 42 may extend about the distal margin of the sidewall. Flange 42 may meet the body of the tub more generally at the location at which the angle of the sidewall changes (i.e., at the location of slope discontinuity. In one embodiment, flange 42 may be rounded, as shown. In this way, lip 40 is quite stiff in the vertical direction i.e., if one considers a flexural modulus as the product EI where E is the young's modulus of the material and I is the second moment of area of the section, in the vertical, or z-direction, which is predominantly the direction of the sidewall, the flexural stiffness is quite substantial given the effective depth of section, in essence the depth of the sidewall; in the out-of-plane direction, be it the x-direction for two sides, or the y-direction for the other two sides, the flexural modulus EI of the section is also substantial given the presence of the curled flange. In a general sense, the lip is relatively stiff in both the vertical and lateral directions.

Considering the second member, namely the lid 24. Lid 24 is a substantially planar member, in which the through thickness, t₂₄, is small relative to both the length, L₂₄ and the width W₂₄. Lid 24 may tend to have a shape corresponding in size and plan form to the underlying tub. As in the instance illustrated, that plan form may be four-sided, and may be rectangular, having a pair of opposed long sides and a pair of opposed short sides, or margins. Lid 24 includes a central spanning portion 48 that is, in essence, a thin membrane. The membrane may have a central relief or embossment, which may carry one or more decorative (i.e., non-functional) design features (not shown). Lid 24 has a first, or inward facing surface, 50, and a second, or outward facing surface 46. Lid 52 has a peripheral margin 54, that includes a mating fitting (or fittings, as may be) 44 defining a land for co-operative engagement with lip 42. For example, the underside of lid 24 may include a pair of first and second, peripherally inner and peripheral outer walls 56, 58 that stand downwardly proud of inwardly facing surface 50. To the extent that wall 58 is outwardly offset from wall 56, a rebate, or accommodation or groove 60 is defined therebetween. Groove 60 is sized to engage lip 40 in an interference fit as noted above. While an arrangement of spaced walls defining a peripheral track or groove is illustrated, a single interference fit wall could be used, with the inside (or, in an alternate arrangement, outside) wall defining a land against which lip 40 may bear. In the further alternative, either one or both of walls 56 and 58 could be discontinuous. That is, either could be an array of spaced abutments or peripherally segregated lands sufficient to grip lip 40, without necessarily forming a continuous peripheral surface. The slot, or groove 60 may fit rather tightly on lip 40, and may be an interference fit in which either one or both of wall 58 and lip 40 are subject to a measure of elastic deflection. It may be that the local flexural stiffness of the groove wall may be softer, or more yielding that the lip, and that lid 24 may be made of a softer (i.e., lower Young's modulus) material in any case. Opposite corners of lid 24 have lifting or prying tabs (i.e., lid disengagement fittings) 62 and 64 which extend proud of the underlyling periphery of tub 22 at flange 42.

The outer surface of lid 24 may also have a seat 68 on the outer surface of spanning member 48, the boundaries of seat 68 being defined by a set of retention fittings or guides, which may also be termed a retainer, or retainers, indicated generally as 70. The retainer fittings 70 may include a three sided horseshoe-shaped peripheral retaining wall 72 having first and second parallel side edge portions 74, 76, and an end wall portion 78. Capture members in the nature of flanges or flange portions 80, 82 and 84 may extend from the distal or top edge of edge portions inwardly to form a three sided channel or slot, or track, or guideway. It may be noted that one end of this peripheral wall is left open, as indicated at 86. It may also be noted that the plane of the guideway is completely separate from, and does not interfere with, the plane or zone, of the peripheral lip for mating with lower portion 22.

The third portion, namely the auxiliary container 26, may have the form of a hollow body, 90, that is equipped with guide followers 92. In this instance, body 90 may be a molded body of substantially rectangular walls, the resulting box-like shape having a length L₉₀, a width W₉₀ and a through thickness t₉₀. The box-like shape may tend to be a rather flat box-like shape that presents two surfaces of rather larger area then the other four sides of the box. That is, there may be spaced apart major surfaces walls 94, 96 that are substantially square or rectangular, those walls being held in their spaced apart condition by a peripheral upstanding sidewall 98 that has long side portions 100, 102, and short side portions 104, 106. One of the side portions, be it portion 106, has a deviation 108, or relief, and a spigot, or tap, or port, or outlet 110, such as a capped spout, by which liquids may be introduced into the internal space defined within hollow body 90, or drained therefrom as may be, and held there by cap 112. The guide followers may take the form of tabs, or extensions 114. For example, it may be convenient for these tabs or extensions to be in the plane of the bottom wall of body 90. That is, one of the major surfaces, which will arbitrarily be named the bottom or lower such surface 96, may have side rail portions 116, 118 that extend laterally beyond long side portions 100, 102. Those side portions may be spaced to run within the clear width between the guides or retainers of lid 24. The guides and retainers may define a sufficiently thick guide channel to accommodate siderail portions 116, 118, and may do so in a slight interference fit. On insertion, side rail portions, which may be considered as guide followers, are trapped between edge portions 74 and 76, preventing lateral translation, (i.e., in the y direction) and between spanning portion 48 and flange portions 80 and 82, preventing vertical translation (i.e., in the x direction). The relationship of these parts also prevents relative rotation between lid 24 and body 90 about any of the x, y, or z axes. Thus only a single degree of freedom remains, namely translation in the x-direction as the guides and guideways mutually engage in sliding relationship. It may be understood that the terminology is somewhat arbitrary: the guides can be on either the lid or the hollow body, and, whichever they may be, the guide followers are on the other of the hollow body or the lid, as may be. Even translation in the x-direction is limited by and end of travel fitting, or abutment, or stop, in the nature of the end wall, and the engaging outwardly extending flange or extension portion 120 of bottom wall 94 as it seats under flange portion 84. In operation with a gentle interference fit, the third member 26 slides neatly along its single degree of freedom track into position on lid 24, generally centered and above tub 22 in a secure, compact package. A thermal storage medium may be contained in hollow body 90. That thermal storage medium may be a phase change material that may employ a thermodynamic phase change as a means of storing energy, either as one whose phase change gives off heat (i.e., is exothermic) or acts as a heat sink. One example of such a medium is water. Hollow body 90 may be filled with water and placed in a freezer. When desired, the container of frozen water may be seated on lid 24 as described, and, given that its largest, i.e, major, surface is placed in close contact with the spanning member, the result is a cooling element mounted to a container which, as one may expect, may be employed to contain objects that a user may wish to keep cool or cold. In other instances, hollow body 90 may be filled with alcohol, or alcohol solutions, including such alcohol solutions or distillates as may be.

In the illustrated embodiment lid 24 has the form and function of an adapter that mates with both lip 40 of lower portion 22, and with the auxiliary container, item 26. The mating functions of each are independent and do not obstruct or interfere with each other. That is, lid 24 forms a peripheral interference fit, which may be a substantially watertight sealing fit, with lip 40. Neither the presence nor the absence of auxiliary container 26 alters this mating relationship. Similarly, auxiliary container 26 mates with a seat defined on lid 24, and this relationship is not altered by the presence of the seal fittings. Lid 24 is substantially planar, and has a local flexural modulus at its peripheral edge that is substantially less than (perhaps less than 1/20^(th) of) the corresponding vertical stiffness of the tub wall and lip. Consequently the mating action of the lid is substantially in the vertical direction—the direction in which the lip seats in an interference fit in the receiving mating groove of the lid; and also, particularly when disengaging, the lid can be flexed in the vertical direction, as when peeled up at the corner. The tangs, or tabs, or extensions at diagonally opposite corners of lid 24 that extend proud of (i.e., overhang) the corner portions of curled flange 42 provide an opening handle, or opening member by which to cause this peeling or bending effect such as may release the grip of the lip in the groove.

Typically, the length and breadth of the auxiliary container are large relative to the through thickness. The length may be more than thrice the through thickness, and the breadth may be more than double the through thickness. In one embodiment, the ration is roughly 6:4:1. In another embodiment the ratio is more on the order of 12:9:1. In most instances the through thickness may tend to be about one inch, and may tend not to exceed about one inch. In terms of presenting a large surface through which to transfer heat, it may be generally helpful for the container thickness to be kept small relative to the other dimensions. The condition of placing one of the large sides against the spanning member may be expressed mathematically. To the extent that hollow body 90 has a nominal or inside volume, V, and may be defined as having a length, a width and a through thickness exclusive of the extending guide or guide follower fittings, a characteristic dimension may be defined, that dimension, d_(L), being the length of the side of a cube of equal volume to volume V. The enclosed volume also has a nominal surface area, A_(Total) which, in the case of the illustrated embodiment is the surface area six-sided box, excluding the guide follower fittings. The side facing the lid (in use) has a surface area A_(s). That side has an hydraulic diameter d_(H), determined according to the formula d_(H)=4A_(s)/P, where P is the perimeter length of the surface. In each case three conditions are satisfied, namely that (i) A_(s) is greater than or equal to ⅙ of A_(Total); (ii) The square root of A_(s) is greater than or equal to the cube root of V (i.e., A_(s)>V^(2/3)); and (c) d_(H) is greater than or equal to d_(L). In the embodiment illustrated, the auxiliary container has a footprint in plan view (i.e., when viewed from above) that is substantially the same as, or perhaps slightly smaller than both the lid and the underlying tub. That is, A_(s) may tend to be 85% as large as the lid surface, or larger, and may tend to have about the same footprint as base wall member 30 of tub 22. In the general case, the through thickness t₂₆ of the auxiliary container is substantially less than the depth of the tub, being less than ½, and generally less than ⅖ of that depth.

Other embodiments may be considered. For example, FIGS. 10 b, 11 b and 12 b are intended to show that the retainer guide members need not be continuous, but may have the form of discontinuous cleats that form a guideway nonetheless. Further, while FIGS. 11 a and 12 a show a re-entrant moulding wall with an upwardly facing peripheral groove 122, FIGS. 11 b and 12 b do not include such a groove. Furthermore, the embodiment of FIGS. 11 b and 12 b shows an engagement groove 124 that has an internal rounded bead, as at 126, such as may tend to pick up against the most distal edge of lip 40 on engagement.

In FIG. 13 there is an auxiliary container 130 that seats on guide fittings 132 of a non-planar mounting body, be it a lid or a tub, indicated generically as 134. The point of the embodiment of FIG. 13 is to illustrate that the seat need not necessarily be planar. In this embodiment, the flask or auxiliary container 130 and the surface to which it mates are formed on a cylindrical surface, which may be the surface of a body of revolution. As with the substantially planar surface of the spanning member 48 in the embodiments described above, the mounting fittings 132 for the flanges 136 of the hollow body of container 130 are formed on one side of the surface (be it planar or cylindrical, and which may be termed a neutral plane, or neutral surface) and the lip engagement fittings (not shown in FIG. 13) are mounted on the other side, such that neither interferes with or otherwise obstructs the other.

In FIG. 14, lid 140 has both internal and external guide fittings 142, 144 such as may permit the auxiliary container, e.g. item 26, to be seated in a secure position either outside or inside lid 140 (or, if provided with two hollow containers, then on both). In each case there is a plane, or a cylindrical surface of revolution, and the guideway fittings lie to one side of that surface while the lid closure fittings lie to the either side of that surface such that the guideway and retention fittings do not obstruct operation of the closure fittings between the lid and the tub. In each case the guideway fittings permit motion on a single degree of freedom, that single degree of freedom defining a direction of linear translation of the one part along the other until the fully seated (or, in the other direction, fully disengaged) position is reached.

In FIG. 15, lid 150 has external fittings 152, 154 that are spaced more narrowly than fittings 80, 82, and tub 160 has internal shoulder fittings 162, 164 (which may be a continuous internal peripheral ledge, or an array of discrete abutments) and the laterally extending flanges 166, 168 of auxiliary container 170 may seat thereupon when lid 150 is closed.

In the example of either FIG. 14 or FIG. 15, it may be that auxiliary container 170 may be mounted on the outside of the lid (be it 140 or 150) when in use with, for example a cooling (or warming) storage medium, and tub 160 full of objects to be cooled (or warmed, as may be), or when auxiliary container 170 is filled with a beverage and tub 160 has other non-potable food, be it dry food or otherwise. However, for storage (or when less food is being carried in tub 160) auxiliary container 170 may be carried inside, forming a smaller overall package for storage when not in use. In that instance, the hollow body may be tapered somewhat in a manner corresponding to the draft angle of tub 160.

In FIG. 16, lid 180 may be free of external mounting fittings for the auxiliary container, and instead the auxiliary container (such as items 26 or 170) is removably mountable to the bottom of tub 182 by means of mounting fittings 184, 186 of the same general nature as the guides and guideways described above. Alternatively, tub 182 may be employed in a combination that includes a lid such as item 40 having external fittings as well, such as may permit alternate positioning of the auxiliary container, or the use of more than one such auxiliary container.

FIGS. 17 a-17 f show a soft-sided insulated container 200 having an upper insulated wall structure defining a first accommodation portion 202, and a lower insulated wall structure defining a second accommodation portion 204. The wall structure may include an inner skin 206, an outer skin 208, and an internal insulating layer or member 210. The inner skin may be an insulating liner. Each of the upper and lower wall structures may have a closure member 212, 214, such as a zipper, by which access to the internal volume or chamber so defined is governed. The closure members are each movable between open and closed positions. The bottom portion 204 may have the same general box-like shape as the container assembly 20 that is to fit therewithin. The structure may be such that closure member 214 of the lower portion extends about three sides of the structure, the fourth side being hinged as at 215 to permit the upper portion to pivot away from the lower portion, exposing opening 216 and giving access to the interior space 218. The height of the sidewall of the lower portion may be approximately the same as the overall height of the assembly of tub 22, lid 24 and auxiliary container 26. Similarly, the breadth and depth of the assembly may fit in a reasonably snug fit within interior space 218. The upper portion 202 may have a generally upwardly narrowing shape, and may have an upper handle 220 by which the package may be carried, with the heavier objects in the tub in the lower compartment. This assembly may typically be a child's lunch box assembly and may have overall dimensions in the range of 4-6 inches in width, 6-8 inches in length, and 8-10 inches in height, exclusive of the handle. Although a soft-sided assembly that hinges in the middle is shown and described, the bottom portion could also be end opening. That is, end panel 222 could be provide with a closure member and a hinge, permitting the hard sided container assembly to slide in from the side, rather than being loaded from the top in use.

In each case, the auxiliary container may be removed and filled with a phase change liquid, which may be water. The auxiliary container may then be placed in a freezer until the liquid is frozen. When the tub is loaded with the object or objects to be cooled, the auxiliary container slides snugly and securely into its seat with one of its major side surfaces in closed engagement with the spanning member of the lid. The elements of the package have a similar size and shape (or footprint) and combine to form a trim secure package. In this instance “similar” may be roughly quantified as being within perhaps 20-25% (or less) of each other in terms of length and width. This package may be placed in a suitable insulated container, such as soft-sided insulated container 30, which may be carried by hand or in a knapsack. Once again, the fit may be relatively snug, which, may be interpreted as being within 20-25% of each other in terms of width, length and overall height, is not rather less, e.g., 10% or less. In other applications, the auxiliary container may be rather larger, and may have a smaller ratio of thickness to length or width (or both), and may provide cooling for such things as dessert squares or other foods carried in the tub.

The principles of the present invention are not limited to these specific examples which are given by way of illustration. It is possible to make other embodiments that employ the principles of the invention and that fall within its spirit and scope of the invention. Since changes in and or additions to the above-described embodiments may be made without departing from the nature, spirit or scope of the invention, the invention is not to be limited to those details, but only by the appended claims. 

1. A container assembly comprising: a base portion, a lid portion, and an auxiliary container; said base portion having a generally rectangular first wall and a peripheral sidewall standing away therefrom, said peripheral sidewall having four co-operating generally four sided portions, said base wall and said sidewalls co-operating to define an open topped box-like tub; said peripheral sidewall having a peripheral lip defining an opening of said box-like tub; said lid portion including a substantially planar spanning member, said substantially planar member having a first face for orientation, in use, toward said tub, a second face for orientation away from said tub, and a neutral plane; said lid portion having a peripheral land facing in the same orientation as said first face of said spanning member, said peripheral land being matingly engageable with said lip of said base portion; said lid being movable between an open position in which said land and said lip are disengaged, and a closed position in which said land and said lip are engaged in said closed position said lid and said base portion defining an enclosed chamber; said auxiliary container having a hollow body, and a port by which liquids may be introduced therewithin, said port having a closure member; said auxiliary container having a length, a breadth, and a through thickness, said length being at least as great as said breadth, and said through thickness being less than one half of each of (a) said length and (b) said breadth; said auxiliary container having a surface for placement next to said spanning member; said lid having a seat for said auxiliary container; one of (a) said lid and (b) said auxiliary container, having at least one guide; the other of (a) said auxiliary container, and (b) said lid, having at least one guide follower, said guide and guide follower being co-operable to direct said auxiliary container into an engaged position in said seat; said lid being engageable with said lip by an engagement motion in a first direction; said auxiliary container being movable into engagement with said seat by motion in a second direction, said auxiliary container being constrained to move in said second direction by said at least one guide and guide follower; said second direction being substantially cross-wise to said first direction; and, when said auxiliary container is mounted in said seat, engagement of said lip with said peripheral land being unobstructed by said auxiliary container, said at least one guide and said at least one guide follower.
 2. The apparatus of claim 1 wherein: said auxiliary container has a substantially rectangular footprint, and includes first and second flange portions extending outwardly from at least two opposed edges of said rectangular footprint; said lid has first and second opposed mating flanges for sliding engagement with said first and second flange portions of said auxiliary container, said flange portions and said flanges defining said at least one guide and said at least one guide follower.
 3. The apparatus of claim 1 wherein said auxiliary container has a phase change thermal storage medium contained therewithin.
 4. The apparatus of claim 1 wherein: said auxiliary container has a first substantially rectangular wall, a second substantially rectangular wall spaced and parallel to said first rectangular wall, and a peripheral wall extending between said first and second substantially rectangular walls; said first wall has first and second extending flange portions standing proud of said peripheral wall, said flange portions defining said at least one guide follower; said lid includes a set of cleats, said cleats defining said at least one guide member, said cleats being mounted to stand proud of said second face of said spanning portion of said lid; said cleats and said flange portions being co-operable in a sliding interference fit.
 5. The apparatus of claim 1 wherein said open-topped box-like tub includes a seat for receiving said auxiliary container therewithin, and, when said auxiliary container is received therein, said lid and lip are unobstructed.
 6. The apparatus of claim 5 wherein said auxiliary container, said lid portion, and said base portion all have generally corresponding footprints.
 7. The apparatus of claim 6, further comprising a soft-sided insulated container housing, said housing including an accommodation of a close fitting size corresponding to said auxiliary container, said lid portion and said base portion as assembled, said soft-sided insulated container housing being made of a wall structure having an inner skin, an outer skin and a layer of thermal insulation therebetween.
 8. The apparatus of claim 7 wherein: said soft-sided insulated container includes a first soft-sided insulated wall portion defining a first compartment and a second soft-sided insulated wall portion defining a second compartment; said first compartment defining said accommodation, said first compartment having a first closure member; said second compartment being mounted adjacent to said first compartment, and having a second closure member governing access thereto, said first and second compartments sharing, and being segregated by, a common wall.
 9. The apparatus of claim 8 wherein said soft-sided insulated container includes a lifting member, and, in use, when hanging from said lifting member, said first compartment is located below said second compartment, and said second compartment narrows from a broad base to a narrow top.
 10. A container assembly comprising: a first member, a second member, and a third member; the first member being a substantially rigid container base portion, said base portion having a bottom and an upstanding peripheral sidewall; said upstanding peripheral sidewall having a margin defining a lip; the second member being a substantially planar lid co-operable with said container base portion, said lid including a peripherally extending land matable with said lip, said lip and said land mating in an elastic interference fit defining a seal such that said lid is co-operable with said container base portion; said third member being a substantially rigid hollow vessel; said third member having an internal volumetric envelope, a nominal enclosed surface and a first surface for placement next to the second member; said first surface having an hydraulic diameter having a magnitude that is greater than the cube root of said internal volume; said first surface having an area greater than one sixth of said nominal enclosed surface; said second member having a seat for receiving said third member, and when so seated, said first surface being next to said second member, said second and third members having between them a co-operable set of guides and guide followers by which said second member is moved between engaged and disengaged positions relative to said seat; and said land is unobstructed by (a) said seat; (b) said guides and (c) said guide followers.
 11. The container assembly of claim 10 further comprising a soft-sided insulated container having a first accommodation sized to receive said first, second and third members as an assembled unit.
 12. The container assembly of claim 11 wherein said soft-sided insulated container has a second accommodation defined therein.
 13. The container assembly of claim 12 wherein said soft-sided insulated container has a first soft-sided insulated wall structure portion in the form of a five-sided open topped box defining said first accommodation, and a second soft-sided insulated wall structure portion having a base, a pair of end walls, and a downwardly opening spanning wall extending between two end walls co-operably joined to define said second accommodation therewithin, said base of said second soft-sided insulated wall structure portion defining a lid of said first soft-sided insulated wall structure portion, said soft-sided insulated wall structure including a first closure member extending peripherally about at least a portion of said base of said second soft-sided insulated wall structure portion, said first closure member being operable to govern opening and closing of said base relative to said five-sided open topped box structure, thereby governing entrance thereto; said base having an edge hingedly joined to said five-sided open-topped insulated box; said end walls having a downwardly broadening form having a crest and a base, said spanning wall being bent to conform to said downwardly broadening form; said second soft-sided insulated wall structure portion including a second closure member governing access thereto; and said soft sided insulated container has a handle mounted at said crest, whereby, when lifted by said handle said first accommodation hangs below said second accommodation.
 14. The container assembly of claim 10 wherein said lid mates with said lip by motion predominantly in translation in a first direction substantially normal to said lid and said substantially rigid hollow member mates with said lid by motion in translation in a direction predominantly parallel to said lid.
 15. A container assembly comprising: a plastic moulded tub having a peripheral lip defining a mouth of the tub; a plastic moulded lid for the tub; and a moulded plastic flask; the lid having a closure fitting for mating with the moulded tub; and the lid having guide fittings; the moulded plastic flask having guide followers for sliding engagement with the guide fittings of the lid; and when the moulded flask is mated to the lid (a) the closure fitting for mating with the tub is unobstructed by the guide fittings and guide followers; and (b) the guide fittings and guide followers are unobstructed by the closure fitting.
 16. The container assembly of claim 10 wherein said closure fitting and said moulded tub engage by relative motion in a direction substantially normal to said lid, and said flask and said lid engage by motion in a direction substantially parallel to said lid.
 17. The container assembly of claim 15 wherein: said lid has a first face oriented to face into said tub, and said closure fitting is oriented in the same direction; and said lid has a second face oriented to face away from said tub, and said guide fittings stand proud of said second face.
 18. The container assembly of claim 15 wherein said tub has at least one abutment fitting defining a seat therein for receiving said flask within said tub without obstructing securement of said lid to said tub.
 19. The container assembly of claim 15 wherein said lid has guideway accommodations for said flask both internally and externally relative to said tub.
 20. The container assembly of claim 15 wherein said tub has a base wall, and said base wall has external fittings for mounting said flask in substantially planar facing relationship thereto outside said tub. 